The present invention relates to an operating member control device of an electronic musical instrument having a manually operated and/or motorized operating unit so as to control parameter data representing various musical elements such as a pitch, a tone color and a volume of a tone, and a sound effect.
An operating unit is disclosed in Japanese Patent Laid Open Specification No. 57-95604 wherein operating member positions thereof can be moved manually and/or by a driving force of a motor so as to preset parameter data of tones.
This operating unit includes electrodes each having a predetermined code pattern, an operating member having a slider which slides on the electrodes, and a drive mechanism which includes a motor for moving the operating member and a torque transmission mechanism. Lever data corresponding to the position of the operating member is read out from the code pattern electrodes and is used as parameter data.
According to this operating unit, the operating member position data extracted from the code pattern electrodes is stored in a preset memory. When the operating member is manually moved, a desired parameter data can be stored in the preset memory. Furthermore, the operating member parameter data corresponding to the current position of the operating member is compared with the preset parameter data representing target position of the operating member read out from the preset memory, and the motor is driven in the forward or reverse direction until the operating member parameter data coincides with the preset parameter data. The operating member can be freely moved to a target position corresponding to the preset parameter data. Therefore, the content of the preset parameter data can be directly observed by the position of the operating member without arranging a special display means. Furthermore, when the operator manually moves the operating member from the current position to another position, the preset parameter data can be updated.
However, in the conventional operating member control device using the operating unit of this type, a control signal corresponding to a difference between the operating member position data representing the current position of the operating member and the preset parameter data is constantly applied to the motor. When the operator manually moves the operating member in one direction, a control signal generator generates a control signal so as to move the operating member in the other direction. As a result, the operating member cannot be easily, manually moved, resulting in inconvenience.